Smoking mixture

ABSTRACT

A smoking mixture comprising a tobacco substitute in admixture with a solid residue obtained by removal of nicotine from Nicotiana Rustica or with a solvent extract of such a residue.

United States Patent [1 1 Anderson et al.

[451 July 15,1975

1 1 SMOKING MIXTURE [75] Inventors: Robert Craig Anderson; Donald Calder; John Cormack Lovie, all of Manchester, England [73] Assignee: Imperial Chemical Industries Limited, London, England 221 Filed: June 24,1974

211 Appl. No.: 482,786

[30] Foreign Application Priority Data July 9, 1973 United Kingdom 32504/73 [52] U.S. Cl. 131/2; 131/143; 131/144 [51] Int. Cl. A24b 15/00; A24b 15/08 [58] Field of Search 131/17, 2,143,144

[56] References Cited UNITED STATES PATENTS 10/1905 Wimmer 131/143 7/1962 Hind 131/143 8/1969 Kirkland 131/2 OTHER PUBLICATIONS The Chemistry and Technology of Tobacco (text) by A. A. Shmuk, published by Pishchepromizdat, Moscow, 1953, Translation by National Science Foundation, pp. 548 and 711 cited.

Primary ExaminerMelvin D. Rein Attorney, Agent, or FirmCushman, Darby & Cushman [57] ABSTRACT A smoking mixture comprising a tobacco substitute in admixture with a solid residue obtained by removal of nicotine from Nicotiana Rustica or with a solvent extract of such a residue.

14 Claims, No Drawings SMOKING MIXTURE This invention relates to smoking mixtures.

In view of the widely held opinion that the smoking of tobacco, especially in cigarette form, can cause lung cancer and bronchitic ailments attention is turning to the provision of smoke-producing substrates which produce less tar and other harmful substances than tobacco, for example to cellulose, oxidised cellulose and particularly to heat-treated cellulose prepared for example by the process described and claimed in United Kingdom Pat. No. 1,113,979.

Unfortunately the smoke from such substrates lacks the flavour of tobacco and in order to provide a palatably acceptable smoke it is necessary either to mix the substrate with tobacco or to discover suitable flavouring material for addition to it. Mixtures with tobacco produce smoke with a health hazard proportional to the tobacco content and the use of flavouring material appears preferable because smaller quantities of flavourant are likely to suffice.

The present invention utilises, as a source of flavourant, a plant species called Nicotiana Rustica. This contains very high proportions (about 14 percent) of nicotine and unlike Nicotiana Tobaccum it has not proved generally acceptable as the basis of smoking materials owing to its extremely strong and unpalatable flavour. Nicotiana Rustica is useful nevertheless as a source of nicotine for use in insecticides and in the fortification of tobacco, reconstituted tobacco and tobacco substitutes.

According to the present invention a smoking mixture comprises a tobacco substitute in admixture with a solid residue obtained by removal of nicotine from Nicotiana Rustica or with a solvent extract of such a residue.

Various methods are known for removing nicotine from Nicotiana Rustica (or indeed from tobacco) none being completely selective in separating nicotine from other constituents. A preferred residue used in the invention is that produced by treating Nicotiana Rustica with alkali (particularly ammonia or potassium carbonate and especially lime) followed by steam distillation or leaching with water to remove the nicotine. Substantially complete removal of the nicotine can be achieved in this way if desired.

As desired, the smoking mixtures of the invention may contain either the said solid residue or a solvent extract therefrom such as may be obtained by extraction of the solid (for example in a Soxhlet apparatus) with a low boiling organic solvent. Suitable solvents include alcohols e.g. ethanol, ketones, e.g., acetone, hydrocarbons, e.g., hexane and chlorinated hydrocarbons, e.g., chloroform.

The expression tobacco substitute means any solid substance which, though not of tobacco origin can be smoked in the same way as tobacco. Tobacco substitutes may be for example of carbohydrate origin, e.g., those described in British Pat. Nos. 1,055,473 and 1,143,500 and US. Pat. No. 3,106,209, namely cellulose, oxidised cellulose and lettuce leaves. Cellulose ethers may also be used, particularly carboxymethyl cellulose and its salts.

Advantageously the tobacco-substitute may be a thermally degraded carbohydrate, made for example by subjecting carbohydrate (particularly cellulose) to a catalysed degradation process at above 100 (e.g.,

100 to 250C as in our UK Pat. No. 1,113,979) until the weight of degraded carbohydrate is less than 90 percent of the weight of the original carbohydrate. A similar substance is obtainable as described in our British Pat. No. 1,289,354 by acid or base catalysed condensation of a compound of the formula:

R COCH CH COR wherein R and R which may be the same or different,

each represents a hydrogen atom or an alkyl, hydroxyalkyl, or formyl group or a precursor of such compound (I).

The amount of solid residue in the smoking composition of the invention may be, for example from 1 to percent by weight of the amount of tobacco substitute, but for best flavour effect the preferred amount is from 5 to 15 percent.

When a solvent extract is used the amount, on a solvent-free basis, may be for example from 1 to 5 percent by weight of the tobacco substitute.

The smoking mixtures of the invention may desirably be fabricated into sheet or filamentary form with the aid of a binder. Other known ingredients of smoking mixtures may be included to impart desired physical properties and burning characteristics. For example, the smoking mixtures may incorporate glowcontrolling catalysts, materials to improve ash coherence and colour, nicotine, other flavourants, medicaments, humectants or film-forming agents. If desired tobacco may also be incorporated.

Binders which may be used for fabrication of the smoking mixtures of the invention are, for example natural gums or pectins or cellulose ethers, especially carboxymethyl cellulose or a salt thereof. For fabrication the ingredients of the mixture, with the solids preferably in a finely divided form, may be mixed with a sufficient quantity of water to produce a slurry which is then fabricated, for example into a sheet by casting on to a surface and drying. The sheet is then shredded to provide material in a form suitable for smoking. When tobacco is incorporated in the mixture it may be as comminuted tobacco, which may be incorporated in the slurry before casting. Alternatively tobacco shred may be blended with the shredded sheet.

Quite surprisingly it is found that despite the unacceptable taste of the smoke from Nicotiana Rustica itself the smoking mixtures of the invention give palatably acceptable smokes and are generally preferred by smokers to comparable mixtures which do not contain any of the solid residue or solvent extract thereof. For this reason, the smoking mixtures of the invention may acceptably be blended with tobacco in higher proportions than the comparable mixtures which do not contain any of the said solid residue or solvent extract thereof. Blends of tobacco with from 30 to 60 percent by weight of the smoking mixtures form a preferred feature of the invention.

The invention is further illustrated by the following Examples in which all parts and percentages are by weight.

Flavour assessments of cigarettes recorded in the Examples were carried out by one of the following procedures, each of which required a group (panel) of people to smoke and comment on the cigarettes.

The first procedure used a group of smokers expecially selected for their high consistent flavour sensitivity and long experience in testing the flavour of tobacco cigarettes. This group, called the Expert Panel, consisted of a small number of the order of 36 people.

The second procedure required a much larger number of panel assessments (minimum number 22; minimum panel size 11) and measured the preference for one cigarette against another. The method was devised on a statistical basis such that the centainty that a preference existed could be stated as a percentage confidence. This panel was called the Statistical Preference Panel.

EXAMPLE 1 1.26 parts of glycerol dissolved in 4 parts of distilled water were mixed with 1.8 parts of sodium carboxymethyl cellulose dissolved in 96 parts distilled water. 5.73 parts of magnesium carbonate (magnesite), 3.35 parts of calcium carbonate, 0.9 parts of bentonite, 4.81 parts of a material made by heating a-cellulose with ammonium sulphamate at 250 until the weight loss exceeded percent and 2.15 parts of a powdered residue obtained after passing steam through a mixture of 70 parts of ball milled Nicotinia Rustica, 20 parts of distilled water and 10 parts of lime for 45 minutes, were added and the whole stirred until homogeneous (about 1 hour).

The slurry was cast on glass plates to form a film on drying with a basis weight of 48-52 grams per square metre.

The film was shredded and made up into a blend containing 50 percent by weight of this shred and 50 percent by weight of flue-cured Virginian tobacco. Cigarettes from this blend were compared with a 50:50 blend of the same tobacco with identically prepared shred not containing any of the powdered residue.

The two cigarettes were compared using a statistical preference panel test and the panel stated a preference for the cigarettes containing the powdered residue with 96 percent confidence.

EXAMPLE 2 4.5 parts of a material made by heating a-cellulose with ammonium sulphamate at 250 until the weight loss exceeded 10 percent was mixed with 90 parts of water and ground in a disintegrator. 2.28 parts of the powdered residue remaining after leaching a mixture of 8 parts of powdered Nicotiana Rustica, 40 parts of water and 1 part of lime with 48 parts of water and drying were then added to this mixture, followed by 1 part of glycerol, 0.34 parts of ammonium sulphate, 0.84 parts bentonite, 2.76 parts of calcium carbonate and 4.8 parts of magnesium carbonate (magnesite). The resulting slurry was stirred for 1.0 minutes and 2.51 parts of sodium carboxymethyl cellulose added and rapidly dispersed.

The resulting slurry was cast and dried to give a film of basis weight 48-52 grams/square metre.

The film was shredded and made into cigarettes which were flavour assessed by a panel of four experts against similar cigarettes not containing any of the powdered residue. A tobacco taste and after-taste were detected in the former cigarette by all panellists whereas no panellist detected any tobacco taste or aftertaste in the cigarettes not containing any of the powdered residue.

EXAMPLE 3 5.24 parts of a material prepared by heat-treating a-cellulose in the presence of ammonium sulphamate at 250 until the weight loss exceeded 10 percent was mixed with parts of water and ground in a disintegrator. 1.18 parts of glycerol, 0.4 parts of ammonium sulphate in 10 parts of water was added to the stirred mix. A dry mixture consisting of 3.22 parts of calcium carbonate and 0.98 parts of bentonite was then added followed by 2.92 parts of sodium carboxymethyl cellulose, 5.58 parts of magnesite and an ethanol extract of the powdered residue obtained by steam distilling Nicotiana Rustica as described in Example 1. The ethanol extract was obtained by Soxhlet extraction of the Nicotiana Rustica residue for 18 hours during which time 5 percent of the residue dissolved. In this Example 0.48 parts of extracted material was added to the slurry. After stirring for 1 hour the slurry was cast and dried to give a film with a dry basis weight of 48-52 g/sq.m.

The film was shredded and made into cigarettes. When smoked these cigarettes had distinct tobacco flavour features.

EXAMPLE 4 Example 3 was repeated except that 0.26 parts of extracted material was added to the slurry instead of 0.48 parts.

The cigarettes when smoked had distinct tobacco flavour features.

EXAMPLE 5 5.25 parts of sodium carboxymethyl cellulose was mixed with 80 parts of water and ground in a disintegrator. 1.4 parts of glycerol and 0.2 parts of potassium acetate in 10 parts of water was added to the stirred mixture. A dry mixture consisting of 6.0 parts of calcium carbonate, 5.4 parts of diatomaceous earth, 0.4 parts of carbon and 0.6 parts of glycerol was then added followed by an ethanol extract of the powdered residue obtained by steam distilling Nicotiana Rustica as described in Example 1. The ethanol extract was obtained by Soxhlet extraction of the Eicotiana Rustica residue for 18 hours during which time 5 percent of the residue dissolved. In this example 0.48 parts of extracted material was added to the slurry. After drying for 1 hour the slurry was cast and dried to give a film with a dry basis weight of 48-52 g/sq.m.

The film was shredded and made into cigarettes. When smoked these cigarettes had distinct tobacco flavour features.

EXAMPLE 6 5.24 parts of a-cellulose was mixed with 80 parts of water and ground in a disintegrator. 1.18 parts of glyc erol and 0.4 parts of ammonium sulphate in 10 parts of water was added to the stirred mixture. A dry mixture consisting of 3.22 parts of calcium carbonate and 0.98 parts of bentonite was then added followed by 2.92 parts of sodium 'carboxymethylcellulose, 5.58 parts of magnesite and an ethanol extract of the powdered residue obtained by steam distilling Nicotiana Rustica as described in Example 1. The ethanol extract was obtained by Soxhlet extraction of the Nicotiana Rustica residue for 18 hours during which time 5 percent of the residue dissolved. In this example 0.48 parts of extracted material was added to the slurry. After stirring for 1 hour the slurry was cast and dried to give a film with a dry basis weight of 48-52 g/sq.m.

The film was shredded and made into cigarettes. When smoked these cigarettes had distinct tobacco flavour features.

What we claim is:

1. A smoking mixture comprising a tobacco substitute selected from the group consisting of cellulose ethers, and thermally degraded carbohydrates in admixture with an additive which enhances the tobaccolike flavor of said substitute, said additive being either a solid residue obtained by removal of nicotine from Nicotiana Rustica or a solvent extract of such a residue from which any toxic solvent is totally removed, said solid residue being obtained by treating Nicotiana with alkali followed by steam distillation or leaching with water to remove the nicotine.

2. A smoking mixture according to claim 1 wherein the tobacco substitute is a thermally degraded carbohydrate.

3. A smoking mixture according to claim 2 wherein the thermally degraded carbohydrate has been obtained by subjecting carbohydrate to a catalysed degradation process at above 100C until the weight of degraded carbohydrate is less than 90 percent of the weight of the original carbohydrate.

4. A smoking mixture according to claim 3 wherein the thermally degraded carbohydrateis thermally degraded cellulose.

5. A smoking mixture according to claim 1 wherein the tobacco substitute comprises cellulose.

6. A smoking mixture according to claim 1 wherein the tobacco substitute comprises a carboxymethylcellulose or salt thereof.

7. A smoking mixture according to claim 1 wherein the solid residue has been obtained by treatment with lime as the alkali.

8. A smoking mixture according to claim 1 comprising said solid residue in an amount of l to 60 percent by weight of the said tobacco substitute.

9. A smoking mixture according to claim 1 comprising said solid residue in an amount of 5 to 15 percent by weight of the said'tobacco substitute.

10. A smoking mixture according to claim 1 comprising said solvent extract in an amount of l to 5 percent by weight of the said tobacco substitute, calculated on a solvent-free basis.

11. A smoking mixture according to claim 1 comprising fabricated into sheet or filamentary form with the aid of a binder.

12. A smoking mixture according to claim 11 wherein the binder is carboxymethyl cellulose or a salt thereof.

13. A process for the manufacture of a smoking mixture in sheet form comprising slurrying with water a tobacco substitute, a binder, a solid residue obtained by removal of nicotine from Nicotiana Rustica or a solvent extract of such a reside, together with any other ingredients, said solid residue being obtained by treating Nicotiana with alkali followed by steam distillation or leaching with water to remove the nicotine, casting the slurry on to a drying surface and then drying to form a sheet.

14. A smoking mixture according to claim 1 wherein the extract is obtained by extracting said solid residue with a low boiling alcohol. 

1. A SMOKING MIXTURE COMPRISING A TOBACCO SUBSTITUTE SELECTED FROM THE GROUP CONSISTING OF CELLULOSE ETHERS, AND THERMALLY DEGRADED CARBOHYDRATES IN ADMIXTURE WITH AN ADDITIVE WHICH ENHANCES THE TOBACCO-LIKE FLAVOR OF SAID SUBSTITUTE, SAID ADDITIVE BEING EITHER A SOLID RESIDUE OBTAINED BY REMOVAL OF NICOTINE FROM NICOTIANA RUSTICA OR A SOLVENT EXTRACT OF SUCH A RESIDUE FROM WHICH ANY TOXIC SOLVENT IS TOTALLY REMOVED, SAID SOLID RESIDUE BEING OBTAINED BY TREATING NICOTIANA WITH ALKALI FOLLOWED BY STEAM DISTILLATION OR LEACHING WITH WATER TO REMOVE THE NICOTINE.
 2. A smoking mixture according to claim 1 wherein the tobacco substitute is a thermally degraded carbohydrate.
 3. A smoking mixture according to claim 2 wherein the thermally degraded carbohydrate has been obtained by subjecting carbohydrate to a catalysed degradation process at above 100*C until the weight of degraded carbohydrate is less than 90 percent of the weight of the original carbohydrate.
 4. A smoking mixture according to claim 3 wherein the thermally degraded carbohydrate is thermally degraded cellulose.
 5. A smoking mixture according to claim 1 wherein the tobacco substitute comprises cellulose.
 6. A smoking mixture according to claim 1 wherein the tobacco substitute comprises a carboxymethylcellulose or salt thereof.
 7. A smoking mixture according to claim 1 wherein the solid residue has been obtained by treatment with lime as the alkali.
 8. A smoking mixture according to claim 1 comprising said solid residue in an amount of 1 to 60 percent by weight of the said tobacco substitute.
 9. A smoking mixture according to claim 1 comprising said solid residue in an amount of 5 to 15 percent by weight of the said tobacco substitute.
 10. A smoking mixture according to claim 1 comprising said solvent extract in an amount of 1 to 5 percent by weight of the said tobacco substitute, calculated on a solvent-free basis.
 11. A smoking mixture according to claim 1 comprising fabricated into sheet or filamentary form with the aid of a binder.
 12. A smoking mixture according to claim 11 wherein the binder is carboxymethyl cellulose or a salt thereof.
 13. A process for the manufacture of a smoking mixture in sheet form comprising slurrying with water a tobacco substitute, a binder, a solid residue obtained by removal of nicotine from Nicotiana Rustica or a solvent extract of such a reside, together with any other ingredients, said solid residue being obtained by treating Nicotiana with alkali followed by steam distillation or leaching with water to remove the nicotine, casting the slurry on to a drying surface and then drying to form a sheet.
 14. A smoking mixture according to claim 1 wherein the extract is obtained by extracting said solid residue with a low boiling alcohol. 